A: Have you seen Li Ling these days?

B: No, she’s gone to Jilin 1. __________ her grandfather.

A: Has she ever been there before?

B: Yes, she lived there before she came here.

A: Have you 2. __________ her?

B: Yes, I’ve just received a letter from her.

A: 3. __________?

B: She said she had a very good time and would 4. __________ there for another week.

A: What else did she say?

B: She also wanted me to give her best 5. __________ to you.

A: It was very nice of her to say so.

共价键、离子键和分子间作用力是物质间的不同作用力，下述物质中只含上述一种作用力的是（　　）

A．干冰

B．氯化钠

C．氢氧化钠

D．碘